THE CACTUS FORESTS OF CENTRAL BOLIVIA 335 



There now remained but one day's ride to Samaipata, 

 where the trail divides one branch leading toward Sucre, 

 and the other to Santa Cruz de la Sierra. The farther east- 

 ward one goes the greener the country becomes. Between 

 the five-thousand-foot elevation of Pampa Grande and 

 Samaipata, which is six thousand feet above sea-level, there 

 are two peaks to be crossed, one seven thousand three hun- 

 dred and twenty-five feet, and the other six thousand seven 

 hundred feet high. The top of the former is known as the 

 Alto de Mairana; it is a cold, dreary little plateau where 

 half a dozen wretched Indians live. The town of Mairana 

 is on the lower plain between the two peaks. Patches of 

 low brush replace the cacti and thorny, arid-region type of 

 vegetation; there is a sufficient water-supply; and the 

 whole country seems to present a transition zone of reviving 

 life between the alternately hot and frigid upland deserts 

 and the green slopes stretching toward Santa Cruz. 



